[The importance of a teleradiographic evaluation of cardiac volume in subjects with the long QT syndrome].

The increase in electrocardiographic QT interval, denominated "long QT" syndrome, is related to syncopes and sudden death during anger, fear, physical effort, or sleep. Its diagnosis is important because mortality rate is high among untreated patients. In this study the author tried to single out, with the help of conventional radiology, some radiological elements belonging to this syndrome. Heart diameters and volume could be determined by means of teleroentgenography in 24 patients affected with "long QT" syndrome. The method employed considerably reduced the factors preventing a correct determination of heart size. In most of the cases examined, heart diameters and volume were increased, the heart had a globose shape with a lifted tip, the second right arch was accentuated, and the space behind the sternum reduced: these elements suggest a volumetric increase in the right sections of the heart. No relationship was found between QT value and increase in heart size. The results suggest the existence of a non-casual relationship between electrocardiographical anomaly and increase in the volume of the right sections of the heart.